This type occurs when the outer layer of the skin comes into contact with certain substances that cause damage to the protective layer of the skin. This type of dermatitis is the most common. Some substances that can trigger irritant contact dermatitis are soaps, detergents, shampoos, bleach, airborne substances (such as sawdust or wool powder), plants, fertilizers, pesticides, acids, alkalis, engine oil, perfumes, and preservatives. , as well as the use of inappropriate hair clippers.